All snakes are carnivorous, but how they capture and kill their prey varies by species. Most of the world's 3,000 snake species are constrictors—squeezing their prey to death. But about 450 species are venomous.

Snake venom is a cocktail of toxic proteins, produced in special glands and delivered through enlarged teeth, or fangs. Some venom kills by clotting blood or destroying tissues. Other venom paralyzes the heart or stops an animal's breathing.

Venom: It's All in the Bite

A cottonmouth senses prey and strikes it with hollow fangs that inject venom.
The prey quickly succumbs to the fast-acting venom.

Which Is Which?

Many people confuse "venomous" and "poisonous." Venomous animals inject a toxic substance; poisonous animals are toxic when they are touched or eaten.